Shimonagata T, Nishimura T, Uehara T, Hayashida K, Saito M, Sumiyoshi T
Department of Radiology, National Cardiovascular Center, Osaka, Japan.
Am J Physiol Imaging. 1990;5(3):99-106.
The purpose of this study was to evaluate the clinical significance of exercise-induced ST elevation in patients who had previous myocardial infarction. Electrocardiographic leads were placed over the infarcted area in 65 patients who had previous myocardial infarction (PMI; isolated left anterior descending coronary artery disease). All patients also had stress thallium scan. Exercise-induced ST changes in leads placed over patients' infarcted areas were compared with the extent of both their myocardial ischemia [thallium ischemic score (TIS)] and the area of their infarcted tissue [defect score (DS)]. The latter was derived from a circumferential profile analysis. In patients who had PMI less than three months after the onset of myocardial infarction (n = 36), the left ventricular ejection fraction (LVEF) and the extent of abnormal left ventricular wall motion did not significantly differ from those in patients with exercise-induced ST elevation (greater than 2 mm, n = 26; less than 2 mm, n = 10). In patients who had PMI more than three months after the onset of myocardial infarction (n = 29), patients with high exercise-induced ST elevation (greater than 2 mm, n = 15) showed left ventricular dyskinesis more frequently than those with low ST elevations (less than 2 mm, n = 14). In addition, the former showed higher DS and lower TIS than the latter. In patients who had PMI less than three months after onset (n = 26), 73% of those with ST elevations with prominent upright T waves (n = 15) also had transient thallium defects in their infarcted areas. They also had higher LVEF and TIS than those with low ST elevations (less than 2 mm, n = 11). These results indicated that exercise-induced ST elevations in leads placed over the infarcted areas are to be interpreted differently depending on the degree of recovery of injured myocardial tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
本研究的目的是评估运动诱发ST段抬高在既往有心肌梗死患者中的临床意义。对65例既往有心肌梗死（PMI；孤立性左前降支冠状动脉疾病）的患者，将心电图导联置于梗死区域上方。所有患者均进行了运动铊扫描。将置于患者梗死区域上方导联的运动诱发ST段改变与其心肌缺血程度[铊缺血评分（TIS）]和梗死组织面积[缺损评分（DS）]进行比较。后者来自圆周轮廓分析。在心肌梗死后发病小于3个月的患者（n = 36）中，左心室射血分数（LVEF）和左心室壁运动异常程度与运动诱发ST段抬高的患者（大于2 mm，n = 26；小于2 mm，n = 10）相比无显著差异。在心肌梗死后发病大于3个月的患者（n = 29）中，运动诱发ST段高度抬高（大于2 mm，n = 15）的患者比ST段低抬高（小于2 mm，n = 14）的患者更频繁出现左心室运动障碍。此外，前者的DS更高，TIS更低。在发病小于3个月的患者（n = 26）中，ST段抬高伴明显直立T波的患者（n = 15）中有73%在其梗死区域也有短暂性铊缺损。他们的LVEF和TIS也高于ST段低抬高（小于2 mm，n = 11）的患者。这些结果表明，置于梗死区域上方导联的运动诱发ST段抬高应根据受损心肌组织的恢复程度进行不同的解读。（摘要截短于250字）
